I used my MGF rims for the first time this weekend with 205/50/R15 race tyres & I can tell you that you will need spacers on each wheel. The offset on the MGF rim is 5mm less than your standard rims so you need a 5mm spacer. On the back there is no tyre rub but the tube that protrubes from the hub is a very tight fit in the centre hole on the MGF rim & may not let the rim sit true without the spacer. Because I only had the 2 spaces & they were needed on the front I put the rims on without them & even though one side was a very tight fit & had to be pushed up against the hub with the nuts it did fit. It took a bit of effort to get the wheel off though.
On the front I have non-standard struts with much narrower springs & without a spacer the 205s on the MGF rim the tyres were jammed up against the base of the locking ring of the adjustable spring base so hard the wheel wouldn't turn. With a 5mm spacer I got occaisional light rubbing in corner & braking which I decided was Ok for the day but I need to go to a bigger spacer for the front. I need to check what the studs will allow but I really need to use a 10mm spacer. I've had issues before eve with the Superlites with some tyre brands hitting these struts depending on the profile of the tyre wall. Factory struts may better or worse with 205/50s but I doubt you will have an issue with 185s.
The nuts I had on my usual Superlites had tapered seats but didn't work on the MGF rims. They were too narrow & chewed the holes up. I bought some bog standard tapers which had a wider seat than my other nuts & they worked fine.
Never say die. At least not while you're still breathing.
